Resilient cable drum

ABSTRACT

A drum for the winding and storage of cable or wire comprising a core and a pair of flanges flanking the ends of the core. The marginal portion of each flange is surrounded by a resilient, nondeformable ring of metal or synthetic plastic which intercepts impact and shock forces applied to the edges of the flanges, thereby protecting the drum from damage.

United States Patent inventor Erich l-lainer Doktor Kamp ll,Leopoldshohe, Germany Appl. No. 828,095

Filed May 19, 1969 Patented July 6, 1971 Priority May 21, 1968 GermanyRESILIENT CABLE DRUM 12 Claims, 17 Drawing Figs.

B6511 75/14 242/117, 118.7,118.6,1l8.4,ll8.5,118.61,118.8,125,

[ 56] References Cited UNITED STATES PATENTS 2,582,597 1/1952 McCaskie242/118.6 2,657,876 1 1/1953 Bieber 242/46.2l 2,944,756 7/1960 Wilson242/117 FOREIGN PATENTS 690,147 6/1930 France 242/1 18.4

909,113 4/1954 Germany." 242/77.4 1,273,640 9/1961 France 242/118.5

Primary Examiner-George F. Mautz Attorney-Michael S. Striker ABSTRACT: Adrum for the winding and storage of cable or wire comprising a core anda pair of flanges flanking the ends of the core. The marginal portion ofeach flange is surrounded by a resilient, nondeformable ring of metal orsynthetic plastic which intercepts impact and shock forces applied tothe edges of the flanges, thereby protecting the drum from damage.

PATENTED JUL e|sm 3.591.104

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PATENTEU JUL si n Fig.6

RESILIENT CABLE DRUM BACKGROUND OF THE INVENTION The present inventionrelates to cable drums, particularly those which are used for thewinding and storage of cable, wire and the like. Conventional cabledrums are usually made from wood, metal or light weight alloys. Becausethe drums are subjected to heavy loading when cable or wire is wound onthem, they must be designed to be structurally stable when loaded. Theymust also be constructed so that they will not roll duringtransportation. The drums must be able to pass through clearancesranging from to 60 centimeters and the flanges must be able to withstandfrequent and repeated contact with hard solid surfaces. The flanges ofwooden drums are frequently unable to endure the impact forces to whichthey are subjected and split, crack or break as a result, thereby makingthe drum unsuitable for further use.

Metallic drums, particularly those made of ferrous metals are stable andwithstand impact and load forces very well. However, these types ofdrums are expensive to manufacture and have a high deadweight. Inaddition, once such drums have been used their return shipment to thesupplier involves a considerable freight cost, especially if the drumsmust be shipped over long distances.

Manufacturing the drums from synthetic plastics has only provided moreproblems. If a hard, high shock-resistant plastic such as polystyrene isused, a sudden shock or impact, such as when the drum is dropped onto ahard surface, tends to break, crack or split the flanges. Drums made ofsoft plastics such as polyethylene, while exhibiting other desirablestructural characteristics, tend to become deformed when subjected to aconstant load for any length of time. Thus, the prior art does notpermit the manufacture of a cable drum which has a relatively lowdeadweight; is stable and can carry heavy cable loads withoutdeformation; and which has impactand shockresistant flanges.

SUMMARY OF THE INVENTION It is an object of this invention to provide animproved cable drum which has a relatively low deadweight, yet which issufficiently stable and capable of carrying heavy cable loads.

Another object of this invention is to provide an improved cable drumwhich has flanges that are resistant to deformation and fracture whensubjected to impact or shock forces.

The improved cable drum comprises a core and a pair of flanges whichflank the ends thereof. Each of the flanges includes a central portionand a marginal portion which surrounds the respective central portion.The marginal portions consist of a material which is more elastic thanthe material of the central portions.

The core of the drum is of substantially cylindrical outline and themarginal portions are resilient rings surrounding the central portions.The material of the core and the central portions is a relatively hardsynthetic plastic material, while the rings consist of a relatively softand resilient synthetic plastic material such as polyethylene.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved cable drum, however, both as to its construction and its methodof operation, together with additional features and advantages thereof,will be best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a cable drum,partly shown in section, wherein one configuration of resilient ringssurrounding the flanges are shown;

FIG. 2 is a side view of the cable drum of FIG. 1, with the internalstructure shown partially in section;

FIG. 3 is an enlarged view of a portion of the elastic ring as seenalong line A-A in FIG. 1;

FIGS. 4 through 16 are cross-sectional views of various forms of theresilient rings which surround the flanges; and

FIG. 17 is a modification of the resilient rings utilizing a metallicband and springs.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. I and 2,there is shown a reel-shaped cable drum comprising a cylindrical core 1and disc-shaped flanges 2 and 3, all of which are made from a relativelyhard and nondeformable plastic. Flanges 2 and 3, which can be of anypolygonal outline, are preferably of circular outline and areconstructed in double-walled fashion as shown in FIG. 1 as described inextensive detail in US. Pat. No. 3,289,972 issued to Erich I-ITa'fner.This double-walled construction protects the drum from damage whichmight occur as a result of thrust loads directed to the external sidesof flanges 2 and 3. Accordingly, an inner flange portion 4 with annularsupports 5, 6 and 7 is connected to core 1 as well as outer flange 8.Flange 8, is also provided with annular supports 5a, 6a and 70 whosesurfaces mate with the corresponding surfaces of the inner flangesupports 5, 6 and 7 respectively. The matching support surfaces offlanges 4 and 8 are adhesively joined to each other by any conventionaladhesive means. In this way the flanges are made stable enough towithstand the large side loads which result from the successive layersof rolled-up cable or wire.

The marginal portions of flanges 2 and 3 are elastic rings 9 which arepreferably of circumferentially complete construction and surround eachof the flanges as shown in FIG. 2. Ring 9 can be made from a relativelysoft and resilient synthetic plastic such as polyethylene. It can alsobe constructed in the form of a metallic ring mounted on shock absorbingmeans such as springs provided between the ring 9 and the centralportion of the flange.

The cross-sectional profile of ring 9 can be in the form of any of amultiplicity of shapes and designs which will be explained in moredetail below.

The central portions of flanges 2 and 3 shown in FIG. 1 are surroundedby ring 9, which in this embodiment is made from polyethylene. FIG. 3illustrates the cross-sectional profile of ring 9 as taken along lineA-A in FIG. 1. Rings 9, which are inserted in annular grooves cut in thesurface of the outermost support 7 of the central portion of flanges 2and 3, extend outwardly beyond the central portions to act as shockabsorbers or bumpers. I

The annular groove into which the elastic ring is inserted can be of anyshape, but more importantly it must be designed so that it willcorrespond to the shape of the elastic ring. FIGS. 4 through 8illustrate various configurations of the elastic rings which can beinserted in the annular grooves of the central portions of the drumflanges. FIG. 4 depicts a hollow ring 13 inserted in a sloped annulargroove. FIG. 5 shows a ring 12 secured to a flange portion 11 and heldin place by a second ring 10. Ring 12 is not inserted in an annulargroove, rather it is mounted on a first side of the angled cornerportion of flange 11 in such a way that it contacts lip 11b. 7

Ring [0, which is fastened to the second side of the corner of flange 11by conventional fastener means indicated by the dotted lines, holds ring12 in place thereby preventing it from being displaced by axialmovement.

FIGS. 6 and 7 illustrate other forms of elastic rings 14 and I5respectively, inserted into grooves cut into the surface of the drumflanges.

FIG. 8 shows an elastic ring 16 which includes a metallic insert 17which serves to prevent damage to the peripheral surface of ring 16.

In each of the above-described configurations illustrated in FIGS. 4through 8 the elastic ring which forms the marginal portion of theflanges of the cable drum has been constructed to be insertable into anannular groove in the flange. In this manner the elastic deformabilityof the particular material from which the ring is made is utilized as ashock-absorbing means because the ring, being of a continuous and closedform, will evenly distribute any stresses applied to it.

In FIGS. 10, 11 and 9, the marginal portion of the flanges has been madein the form of a closed inner ring having projections extendingoutwardly therefrom. FIG. depicts a ring 19 with hollow projections 22extending therefrom, in which the hollowed portions are somewhattriangular in shape. FIG. 11 shows a ring with hollow projections 23,the hollow portions being of circular shape. FIG. 9 illustrates a ring18 having solid projections 21, the ends of which are rounded.

In FIG. 12, the marginal portion of the flange is in the form of a ring24 having hollow projections which extend inwardly from ring 24.

The configurations of the elastic rings shown in FIGS. 13, 14 and 15 areeach constructed in the form of a band whose width exceeds its thicknessand which has recesses provided in the interior portion of the band. InFIG. 13, the recesses are in the form of a trapezoid when the band is inan unstressed condition; in FIG. 14 the recesses are rectangular-shaped;and in FIG. 15 the recesses are of circular shape.

Another possible form of the elastic ring is illustrated in FIG. 16where the ring is of an undulating or wave-shaped outline.

Still another configuration of the elastic ring is depicted by FIG. 17where the marginal portion of the flange includes a resilient metallicring 29 mounted on radially acting springs 30 which are interposedbetween ring 29 and flange 33. A guide pin 31 is affixed to ring 29 andis slidably received in and guided by recess 32 in flange 33.

A further modification of this arrangement would be to use rubber orplastic pads or supports in place of the springs.

In any of the above-described configurations, the principle of operationof the resilient cable drum remains the same. Thus, regardless of thesource of external shock or impact forces, such as from dropping onto ahard surface, or contact with other drums, the resilient rings formingthe marginal portion of the drum flanges intercept, absorb anddistribute any forces applied to the edges of the flanges, thusprotecting the remaining central portion of the flange from damage.

The use of the resilient rings to protect the flanges allows the coreand the central portion of the flange to be made from a syntheticplastic such as polystyrene without the risk of cracking or splittingoccurring in the core of central portion of the flange. Likewise, usingsynthetic plastic for the core and central flange portion reduces thedeadweight of the cable drum without sacrificing the required stability.

The resilient polyethylene rings permit the cable drum to be loaded andstored for extensive periods of time without the rings being deformed asa result of the cable load. When the load is removed from the drum therings will reassume their original shape and will still retain theirresilient character.

A particular advantage of the present invention is that the resilientrings can be replaced whenever necessary, thus greatly extending theperiod of time in which the cable drums can be reused as well asreducing the cost of replacement of damaged or worn drums.

It is to be understood that each of the above-described elements, or twoor more together, may also find a useful application in other types ofcable drums which differ from the type described above.

While the invention has been illustrated and described as embodied inthis resilient cable drum, it is not intended to'be limited to thedetails shown, since various modifications and structural changes may bemade without departing in any way from the spirit of the presentinvention. I

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this invention.

What I claim as new and desire to be protected by Letters Patent is setforth in the appended claims:

1. Cable reel, comprising a cylindrical core; disc-shaped flangesmounted on said core and defining with said core a space for cable, saidcore and flanges consisting of a hard resin; and an elastic ring mountedon the periphery of each of said flanges, said ring consisting of asofter resin than said hard resin and being profiled both axially andradially so that each ring has ribs and cavities, thereby increasing itsflexibility and ability to absorb shocks without damage to itself, theflanges or the core.

2. A cable reel as defined in claim 1, wherein each of said elasticrings has an internal surface and each of said flanges has an externalsurface adjacent to the corresponding ring, one of said surfaces havingat least one annular groove receiving at least a portion of the othersurface.

3. A cable reel as defined in claim 1, wherein said discshaped flangesare composed of polystyrene.

4. A cable reel as defined in claim 1, wherein said softer resin ispolyethylene.

5. A cable reel as defined in claim 1, wherein at least one of saidelastic rings has outwardly extending projections.

6. A cable reel as defined in claim 5, wherein at least some of saidprojections are hollow.

7. A cable reel as defined in claim 5, wherein at least some of saidprojections are solid.

8. A cable reel as defined in claim 1, wherein at least one of saidelastic rings includes a circumferentially complete outer part andprojections extending inwardly therefrom,

9. A cable reel as defined in claim 1, wherein the width of at least oneof said elastic rings exceeds substantially the thickness thereof.

10. A cable reel as defined in claim 1, wherein at least one of saidelastic rings is provided with recesses.

11. A cable reel as defined in claim 1, wherein at least one of saidelastic rings is of undulate cross-sectional outline.

12. A cable as defined in claim 1, wherein at least one of said elasticrings comprises a first ring of synthetic plastic material and a secondring consisting of metallic material surrounding said first ring.

1. Cable reel, comprising a cylindrical core; disc-shaped flangesmounted on said core and defining with said core a space for cable, saidcore and flanges consisting of a hard resin; and an elastic ring mountedon the periphery of each of said flanges, said ring consisting of asofter resin than said hard resin and being profiled both axially andradially so that each ring has ribs and cavities, thereby increasing itsflexibility and ability to absorb shocks without damage to itself, theflanges or the core.
 2. A cable reel as defined in claim 1, wherein eachof said elastic rings has an internal surface and each of said flangeshas an external surface adjacent to the corresponding ring, one of saidsurfaces having at least one annular groove receiving at least a portionof the other surface.
 3. A cable reel as defined in claim 1, whereinsaid disc-shaped flanges are composed of polystyrene.
 4. A cable reel asdefined in claim 1, wherein said softer resin is polyethylene.
 5. Acable reel as defined in claim 1, wherein at least one of said elasticrings has outwardly extending projections.
 6. A cable reel as defined inclaim 5, wherein at least some of said projections are hollow.
 7. Acable reel as defined in claim 5, wherein at least some of saidprojections are solid.
 8. A cable reel as defined in claim 1, wherein atleast one of said elastic rings includes a circumferentially completeouter part and projections extending inwardly therefrom.
 9. A cable reelas defined in claim 1, wherein the width of at least one of said elasticrings exceeds substantially the thickness thereof.
 10. A cable reel asdefined in claim 1, wherein at least one of said elastic rings isprovided with recesses.
 11. A cable reel as defined in claim 1, whereinat least one of said elastic rings is of undulate cross-sectionaloutline.
 12. A cable as defined in claim 1, wherein at least one of saidelastic rings comprises a first ring of synthetic plastic material and asecond ring consisting of metallic material surrounding said first ring.